Abstract
Modern surgery and health care have a strong demand for various prosthetic devices. One can separate between dense high strength permanent implants like superalloys and titanium, and in contrast to those the biodegradable porous bioceramics are partially or fully transformed to natural hard tissue structures by solution/reprecipitation mechanisms. Advanced manufacturing processes such as additive manufacturing technologies have the potential to ensure improved patient care with tailored or customized implants. In this context, bioceramics such as calcium phosphates and bioactive glasses are of particular importance because of their resorption behavior and interface biochemistry. These degradable materials allow a rapid ingrowth of the implant into the bone by the stimulation of osteoblast cells. The requirements for bone grafts are sometimes contradictory, for example, mechanical strength and high porosity. This study therefore explains the production of scaffolds using the inkjet three-dimensional (3D) printing process. The bioceramic raw materials were processed by spray dry granulation to get spherical granules with a suitable flowability for the 3D printing process. The powders were characterized using a scanning electron microscope and particle size distribution measurements, and the flowability was determined by calculation of the Hausner ratio. The porosity of the sintered structures, which was up to 70%, was measured by mercury porosimetry. Sintering curves were determined on the basis of differential thermal analysis/thermogravimetric analysis measurements. The surface characterization was carried out by white light interferometry.
